Studies have identified that, in Amazonian Forest communities, relatively few species contribute disproportionately to large number of individuals (HA, hyperdominance in abundance, i.e. most common species that hold 50

With the increase in deforestation associated with the need to reconcile conservation and food production, agricultural mosaics are of great importance in maintaining biodiversity. This study aimed to compare the shade-tolerant plants diversity partition pattern and the conservation value (CV) presented by land-use types found in three vertical strata (upper, middle, and lower) of six agricultural mosaics in the eastern Amazon. Additionally, we hypothesized that agricultural mosaics with lower forest cover, with lower heterogeneity of land-uses, and drier areas have lower shade-tolerant plants diversity, and CV of land-use types. Plant surveys were carried out in family farming mosaics with fixed plots; a matrix of species abundance per plot was set up for each mosaic and stratum. Additive partition and absolute contribution analyze were applied to each matrix; and CV of the land-uses for gamma richness was calculated. Factors were tested using generalized linear models and simple linear regression. Our results indicate that there is a diversity pattern that is repeated in the strata and agricultural mosaics. Beta diversity, especially among land-use types, is the one that most contributes to the diversity. Habitat heterogeneity is very important for the conservation of shade-tolerant species, but it is not the number of different land-use types but what these land-uses are. Land-uses with low CV do not add diversity to the mosaic. Consequently, the quality of the environmental matrix is very important. This information will be useful in providing baseline data on the management of agricultural mosaics in the eastern Amazon.

After forest suppression in mining areas, deterioration of stocked tropical hardwoods occurs at different rates and levels. Prioritizing logs to avoid wastage is challenging because the wide interspecific variability of wood traits makes natural resistance unpredictable. This work aimed to compare the biodeterioration of four Amazonian hardwoods from a mining stockyard to arboreal termite attacks over six weeks under laboratory conditions. The woods' chemical composition, anatomy, basic density, and crystallinity were determined. Mass loss and visual diagnosis of the specimens supported the biodegradability analyses. The species showed a wide range of mass loss after six weeks: Jacaranda copaia (pará-pará) - 15,2 %; Pseudopiptadenia suaveolens (timborana) - 0,8 %; Aegiphila integrifolia (tamanqueira) - 5,2 %; and Euxylophora paraensis (pau amarelo) - 0,5 %. Biodegradation did not stabilize over time for the lowest-density species. The crystallinity indicated the initial degradation of amorphous wood components, followed by a non-selective feeding mechanism. Gathering all species, increased extractive and lignin levels, fiber wall thickness, and basic density favored the natural wood resistance, oppositely to large vessel elements. The much lower basic density of J. copaia explains its lowest natural resistance. Wall thickness, pore diameter, and density overcame chemical composition on wood biodegradability. Low-density hardwoods stocked in mining yards are a priority for proper destinations.

ABSTRACT Measurements of biodiversity can be used to assess the scale of anthropogenic impact and predict species loss. A great number of diversity measures exist involving species richness and relative abundance that differ in how they are calculated. The choice of the adequate biodiversity measure to compare biological communities poses a challenge. The aim of this study was to evaluate the ability of 26 diversity measures to differentiate land cover types in the eastern Brazilian Amazon. Diversity was inventoried and quantified in three vertical strata in six locally dominant land cover types: primary and secondary forests, agroforestry systems, oil palm plantations, annual croplands and pastures. No diversity measure was able to differentiate all land cover types in every stratum. Fisher’s alpha was able to differentiate cover types in the middle and upper strata, while Smith-Wilson and Jentsch’s mixture quotient were able to differentiate in the lower and upper strata, and heterogeneity indices only differentiated in the upper stratum. The distinction and ranking of plant diversity among land covers depended on the diversity measure chosen. The number and types of land cover and vertical strata were a key factor in the ability of the diversity measure to differentiate among them.

Fragmentation creates heterogeneous landscapes with different interactions and trajectories. In this scenario, the understanding in how forest fragment sizes influence forest species patterns can lead the way for biodiversity management and conservation in agricultural landscapes. The aim of this study was to compare the density and the diameter distribution of Bertholletia excelsa, Carapa guianensis and Cedrelinga cateniformis among fragments of different sizes, located at the Agro-Extractivist Settlement Project Praialta Piranheira, Pará State, Brazil. Data were collected from adult and sapling trees in six forest fragments. Adult and sapling density was compared among fragment sizes by the Mann–Whitney test, while diameter distributions were compared by a summary statistic calculated using the scores of a PCA produced with the results of the binomial logit model between tree DBH and the cumulative DBH proportions. The density of adult trees of three species is similar among different-sized fragments. Only the saplings of C. cateniformis showed a significant difference in density among fragment sizes. The DBH distribution of adults, for all three species, seems to also not respond to fragmentation, since the differences in the DBH distribution curves among fragments were large. The results of this study suggest that in areas established for agroextractivism, all fragments (large and small) no longer have sustainable populations (except only one C. guianensis population), probably due to anthropic pressure exerted by agroextractivism. So, it is important to ensure the structural and environmental quality of the forest fragments for the conservation of the species.

Many personal cleansing products contain microplastics threatening coastal habitats, deep sea, as well as freshwater lakes. Non-pollutant biomasses with natural abrasiveness are potential substitutes for scrub-type cosmetics. This study sought to explore the potential of applying crabwood seed bagasse from Amazonia as an exfoliating agent of skincare soaps. The raw feedstock was characterized by chemical composition and particle size distribution. The morphologies of the crabwood particles and commercial exfoliating agents were compared. Thermal pretreatments were carried out in an attempt to make the particles inert. It was verified that crabwood particles contain above 50% of non-structural organic components in their mass. The high heterogeneity of particle size allowed selecting portions with dimensions comparable to commercial products, between 0.3 and 0.4 mm. The rough surface of crabwood particles was similar to those of other natural plant exfoliating agents suitable for intense skin exfoliation. Thermal pretreatments only partially volatilized non-structural components. The release of oil traces, which contains mainly palmitic and oleic acids, led the pH of the water to an unacceptable level (≤ 5.0), discouraging the direct application of crabwood bagasse in the skin. Nevertheless, when added to non-ionic surfactant based-soaps, pH remains adequate for skincare (≈ 6.0). The smaller particles (average diameter of 0.3 mm) submitted to the most drastic thermal pretreatment, 140 °C for 48 h of exposure, resulted in liquid skincare soaps with better properties. The crabwood particles’ potential to be added as an exfoliating agent in skincare soaps was confirmed.

ABSTRACT Shade-tolerant forest species are among the most susceptible to habitat loss in agricultural mosaics, where a variety of croplands is connected to forests at different levels of anthropogenic disturbance. We aimed to evaluate the community similarity of shade-tolerant species among different land use types across agricultural mosaics with different levels of disturbance. The study was conducted in three municipalities in southern and southeastern Pará state, in eastern Amazonia. A multiple-community similarity measure based on the Horn similarity index was used to compare land use types and assess the resilience of shade-tolerant species towards forest loss and disturbance at the landscape level. High shade-tolerant species similarity was found between mature forest fragments that underwent different levels of disturbance in all three agricultural mosaics, but secondary forests had lower similarity with mature forest in the most fragmented and altered mosaic. Shade-tolerant species showed very low density in croplands, but the same group of species seemed to colonize agricultural fields of annual crops and clean pasture, as they showed high community similarity. Another group of species was present in invaded pastures, probably due to the effects of time since land abandonment after woody species colonization. Mixed tree plantations were more similar to mature and secondary forests than other types of croplands. Shade-tolerant species similarity was higher among land use types inserted in agricultural landscapes that maintained conserved forest fragments. Our results suggest that the conservation of mature forests and landscape connectivity are crucial to the maintenance of shade-tolerant species in agricultural mosaics.

O objetivo deste estudo foi avaliar as modificações de propriedades físicas das madeiras de três espécies tropicais de interesse comercial por tratamentos térmicos conduzidos com diferentes temperaturas e tempos de exposição ao calor. Amostras de madeira de Pouteria caimito, Protium altissimum e Jacaranda copaia foram submetidas a modificações térmicas a 180 e 240 °C, ambas por 1 e 2 h. Foram avaliadas redução de massa, densidade básica e contração volumétrica das madeiras. O tratamento de 2 h a 240 °C causou maior redução de massa para todas as espécies. Pouteria caimito e Protium altissimum não apresentaram diferença significativa na densidade básica e contração volumétrica entre os tratamentos térmicos. A redução de massa, que confirma a efetividade dos tratamentos térmicos, aliada à manutenção da densidade é básica, é benéfica para a qualidade das madeiras. Jacaranda copaia apresentou maior estabilidade dimensional, mas foi mais afetada pelas variações dos tratamentos com diminuição da densidade básica da madeira quando submetida a 180 ºC por 1 h e 240 ºC por 2 h. A secagem das madeiras não tratadas, assim como os tratamentos térmicos, diminui a capacidade de adsorção de água e o volume saturado, resultando em contrações volumétricas similares às das madeiras termicamente tratadas. Palavras-chave: secagem da madeira; hornificação; densidade básica; contração volumétrica. Basic density and dimensional stability of tropical woods modified by thermal treatments ABSTRACT: This study aimed to evaluate the wood physical properties’ modifications from three commercially interesting tropical species by thermal treatments carried out with different temperatures and heat exposure times. Wood samples of Pouteria caimito, Protium altissimum, and Jacaranda copaia were submitted to thermal modifications at 180 and 240 °C, both for 1 and 2 h. The mass reduction, basic density, and volumetric contraction were evaluated. The treatment of 2 h at 240 °C caused the highest mass reduction for all species. Pouteria caimito and Protium altissimum did not significantly differ in basic density and volumetric contraction of wood among thermal treatments. The mass reduction, which confirms the effectiveness of thermal treatments, allied to the maintenance of basic density, benefits the wood quality. Jacaranda copaia showed the greatest dimensional stability, but it was the most affected species by the variations of thermal treatments with decreases in basic wood density when submitted to 180 ºC for 1 h and 240 ºC for 2 h. The drying of the samples, as well as the thermal treatments, may decrease the water adsorption and saturated volume, resulting in volumetric contractions similar to those of thermally treated samples. Keywords: wood drying; hornification; basic density; volumetric contraction.

In the recent decades, many studies have shown the important role of agroforestry, and particularly homegardens, in food supply, but few studies conducted in the Amazon include regional coverage and/or a large number of samples. This makes a more thorough assessment of the importance of these agroecosystems in agrobiodiversity conservation difficult. The objective of the present study is to assess the factors that determine the floristic composition and tree and palm diversity of homegardens at different spatial scales in the Central Amazon. 334 homegardens were sampled in rural and urban areas of 14 municipalities in the state of Pará. Owners were interviewed for the collection of socioeconomic data. A total of 16,049 individual tree and palm were recorded, distributed in 108 species. Most species were fruit bearing. The correlations between socioeconomic and environmental factors and the floristic gradient established in each ordination were significant only at the local scale. Species richness was influenced by factors related to family income, homegarden size, and topographic environment. The criteria for selecting the species comprised in these homegardens are aimed at the food security of the families that own the homegardens. Thus, the floristic composition of homegardens in the Central Amazon is more strongly influenced by owners’ decisions at a local level than by socioeconomic and environmental factors at broader scales. The importance of homegardens to food security and the autonomy of Amazon families indicate that public policies should be designed to stimulate more diverse production systems as a strategy to strengthen family agriculture and agrobiodiversity conservation in the Central Amazon.

Most tropical landscapes are mainly composed of dynamic mosaics involving multiple land uses. Different histories of land use management can lead to different successional paths. The aim of this study was to determine if there is a successional floristic gradient related to land use types and how these gradients change across three rural mosaics in Eastern Amazon. We also investigated what are the indicator species across mosaics and land use types and how they change through succession. Five sampling points were established in nine family farms at each mosaic. A detrended correspondence analysis was used to reveal the successional gradient. A multivariate regression tree was used to analyze differences in floristic composition between mosaics and land uses. Floristic similarity between land uses formed successional gradient at the mosaics, in which agricultural land uses represent the early stages of secondary succession and forests represent more advanced stages. Total number of species and total number of shade-tolerant species were correlated with advanced successional stages in all mosaics, but pioneer trees were also correlated with advanced stages in fragmented mosaics. Each mosaic had a distinct successional series due to different management approaches. Where the matrix was mainly composed of forest fragments and the human intervention period was shorter, land use types were more similar to one another as they were grouped into fewer successional stages. Thus, the floristic similarity between land use types appears as an indicator of successional advancement across the mosaics and help determine the regenerative capacity of those areas.

We studied the tree-regeneration patterns in three distinct agricultural settlements in the Eastern Amazon to test the influence of land-use mosaics. The following questions are addressed: are the floristic structure and composition of regenerating trees affected by the various land-use types applied in the agricultural settlements? Do tree-regeneration patterns respond similarly to distinct land-use mosaics? Is there a relationship between tree regeneration and soil characteristics among the land-use types? The regeneration was inventoried at 45 sampling points in each settlement. At each sampling point, fourteen soil variables were analyzed. Nine different land-use types were considered. The floristic structure and composition of the settlements showed differences in the density of individuals and species and high species heterogeneity among the land-use types. The maximum Jaccard similarity coefficient found between land-use types was only 29 %. Shade-tolerant species were the most diverse functional group in most land-use types, including pasture and annual crops, ranging from 91 % of the number of species in the conserved and exploited forests of Travessão 338-S to 53 % in the invaded pastures of Maçaranduba. The land-use types influenced significantly the floristic structure and composition of regenerating trees in two agricultural settlements, but not in third the settlement, which had greater forest cover. This finding demonstrates that the composition of each land-use mosaic, established by different management approaches, affects regeneration patterns. Tree regeneration was related to soil characteristics in all mosaics. Preparation of the area by burning was most likely the determining factor in the differences in soil characteristics between forests and agricultural areas.

http://dx.doi.org/10.5902/1980509815736Diante da importância ecológica que as florestas ciliares representam para o equilíbrio ambiental, este estudo objetiva indicar espécies nativas para serem usadas na recomposição de florestas ciliares degradadas existentes na sub-bacia do Rio Peixe-Boi. Foram inventariadas todas as árvores e arbustos com diâmetro a 1,30 m do solo > 5 cm em dez áreas de floresta secundária e seis de floresta de igapó. Os dados foram analisados pela Análise de Componentes Principais (ACP) e as espécies avaliadas silviculturalmente através de revisão bibliográfica. As áreas de igapó tiveram baixo índice de riqueza e diversidade de Shannon, quando comparado com os dados das florestas secundárias. A composição florística dos igapós foi bem heterogênea, e há maior similaridade florística entre áreas de maior proximidade geográfica. As florestas secundárias tiveram grande abundância de indivíduos, alta riqueza, diversidade e equabilidade e foram agrupadas em função da proximidade geográfica e da idade, o que está diretamente ligado ao estádio sucessional. A análise ACP estabeleceu a importância ecológica de 29 espécies arbóreas, contudo, foram encontradas informações silviculturais de apenas dez espécies. Por apresentarem grande importância ecológica e técnicas silviculturais viáveis e disponíveis na literatura, as espécies de igapó Carapa guianensis, Pachira aquatica, Spondias mombin, Tapirira guianensis e Virola guianensis são as mais indicadas para a recomposição dessas áreas, em associação com as espécies Inga edulis, Jacaranda copaia, Pseudopiptadenia psilostachya, Simarouba amara e Vismia guianensis de floresta secundária, que podem ser plantadas nas áreas de bordas e adjacentes às florestas de igapó.

This study aims to indicate native species to be used in the restoration of degraded riparian forests in the subwatershed of Peixe-Boi river. All trees and shrubs with diameter at breast height (DBH) > 5 cm were inventoried in ten areas of secondary forest and six areas of igapo forest. The results were analyzed by Principal Component Analysis and the silviculture of the species was assessed by literature review. In Igapo areas 66 species were found; the areas had low richness and low diversity index of Shannon, when compared with data from the secondary forests. The floristic composition was heterogeneous, and the floristic similarity is higher between areas that are closer geographically. In the secondary forests were found 175 species; the areas showed high abundance of individuals, high species richness, diversity and evenness. Secondary forests were separated according to geographic proximity and age, which is directly linked to the successional stage. The PCA analysis established the ecological importance of 29 tree species; however only ten species had enough silvicultural information. Due to a greater ecological importance and viable silvicultural techniques available in the literature, Carapa guianensis, Pachira aquatica, Spondias mombin, Tapirira guianensis and Virola guianensis are the most suitable species to restore the degraded areas, in association with Inga edulis, Jacaranda copaia, Pseudopiptadenia psilostachya, Simarouba amara and Vismia guianensis of the secondary forests, that can be planted in the borders and in the nearby areas of igapo forests.

This study aims to indicate native species to be used in the restoration of degraded riparian forests in the subwatershed of Peixe-Boi river. All trees and shrubs with diameter at breast height (DBH) > 5 cm were inventoried in ten areas of secondary forest and six areas of igapo forest. The results were analyzed by Principal Component Analysis and the silviculture of the species was assessed by literature review. In Igapo areas 66 species were found; the areas had low richness and low diversity index of Shannon, when compared with data from the secondary forests. The floristic composition was heterogeneous, and the floristic similarity is higher between areas that are closer geographically. In the secondary forests were found 175 species; the areas showed high abundance of individuals, high species richness, diversity and evenness. Secondary forests were separated according to geographic proximity and age, which is directly linked to the successional stage. The PCA analysis established the ecological importance of 29 tree species; however only ten species had enough silvicultural information. Due to a greater ecological importance and viable silvicultural techniques available in the literature, Carapa guianensis, Pachira aquatica, Spondias

This study evaluates weed dynamics during the first 4 years (2008–2011) of the implementation of an agroforestry system in the municipality of Tomé-açu in the state of Pará, Brazil. The study was conducted in a degraded pasture of Brachiaria humidicola, and treatments (T) included mixed plantations of oil palm with short-cycle leguminous species (T1) with the inclusion of manioc in T2 and forest species and palm trees in T3. In 2008, a floristic survey was conducted in 12 plots of 2 × 2 m per treatment. In 2009, herbicide was applied to one half of the area in each treatment. A total of 19,367 individuals of height <1.5 m were surveyed, of which 51 % were B. humidicola and 21 % were leguminous species that had been planted. Overall, an increase in plant density was observed between 2009 and 2010, followed by a decrease over the following year in areas without herbicide and a tendency for high densities to persist in areas with herbicide. Species richness increased over the study period in all areas (with or without herbicide), which might be related to habitat availability resulting from the reduced density of B. humidicola due to the effects of the herbicide, the leguminous species planted and the development of the agroforestry system. The association of short-cycle leguminous plants with afforestation appears to be an effective method for controlling weeds in the absence of herbicides.